There are known in the art methods for managing information on friends who meet via a social networking service (SNS) or an online game.
An exemplary embodiment provides an information-processing system comprising one or more information-processing devices and a server, wherein: a first information-processing device is configured to send to the server, identification information of another user registered by executing a first program; the server is configured to store in a storage unit, the sent identification information of the other user; the first information-processing device or a second information-processing device different from the first information-processing device is configured to, for presenting to a user by executing a second program different from the first program, receive the identification information of the other user stored in the storage unit or another item of identification information corresponding to the identification information of the other user; and the identification information of the other user is registered in the first information-processing device as friend information of the user based on a mutual agreement between the user and the other user.